Base station device, control station device, and transmission power control method

ABSTRACT

A total-transmission-power measurement section  113  measures a total-transmission-power-value output from a transmitting RF circuit  112,  and outputs the measured value to a total-transmission-power comparison section  152.  A reference-total-transmission-power setting section  151  outputs a reference total-transmission-power-value, which is a target of the total-transmission-power-value of a base station, to the total-transmission-power comparison section  152.  The total-transmission-power comparison section  152  outputs instructions to reduce allowable transmission-power-values to allowable-transmission-power setting sections  153  of users 1–n, when a value obtained by subtracting of the reference total-transmission-power-value, which has been input from the reference-total-transmission-power setting section  151,  from the total-transmission-power-value input from the total-transmission-power measurement section  113  exceeds a predetermined value. The allowable-transmission-power setting sections  153  decide appropriate allowable transmission-power-values, based on the instructions input from the total-transmission-power comparison section  152,  and output the decided value to individual-transmission-power comparison sections  106.

TECHNICAL FIELD

The present invention relates to a base station apparatus, a controlstation apparatus, and a method for controlling transmission power, and,more particularly, relates to a base station apparatus, a controlstation apparatus, and a method for controlling transmission power,which are used in a digital radio communication system.

BACKGROUND ART

In CDMA communication, there is a so-called distance problem that asignal transmitted by a communication terminal at a short distancebecomes strong interference with signals transmitted by othercommunication terminals, as a plurality of communication terminals usethe same radio frequency band. There is transmission-power-control inorder to solve the distance problem. In the transmission-power-control,a base station apparatus makes instructions so that received levels ofsignals transmitted from each communication terminal become apredetermined level.

And, in the transmission-power-control of downlink signals transmittedfrom the base station apparatus to communication terminals, thecommunication terminals measure received SIRs of pilot symbols, and sendtransmission-power-control instructions to the base station apparatusbased on the measured results. As the base station apparatus controlsthe transmission power based on the above transmission-power-controlinstructions, and transmits signals, the communication terminals mayreceive signals with a desired received level.

A conventional radio communication apparatus will be described, using adocument, “Study on a transmission-power-control method usingfollowing-up control of fluctuations in instantaneous values in DS-CDMAdownlink channels” (The Institute of Electronics, Information andCommunication Engineers, Technical Report AP96-148, EMCJ96-83,RCS96-162, MW96-188 (1997–02)). This document has disclosed atransmission-power-control method in the CDMA. Hereinafter, thedisclosed contents will be described.

In the transmission-power-control, measurement of SIR representingreceived quality, and increase or decrease of the transmission power arecyclically performed every one slot (with a period of 0.62.5 ms). Inthis case, after a measured SIR and a target SIR are compared, aninstruction to reduce the transmission power is sent to a base stationapparatus (transmission side) when the measured value is larger, and aninstruction to increase the transmission power is sent to the basestation apparatus when the measured value is smaller. The base stationapparatus increases or decreases the transmission power according to theabove instructions.

And the base station apparatus performs outer-loop control, consideringthat the target SIR depends on the environments of communicationterminals in order to obtain the required quality (FER: Frame ErrorRate). Specifically, FER is measured in the first place, using dataafter decoding. After the measured FER and the target FER are comparedevery several frames, the target SIR is raised when the measured valueis larger, and the target SIR is decreased when the measured value issmaller.

As described above, in the conventional technology, thetransmission-power-control instructions are sent to the base stationapparatus based on SIRs measured at the communication terminals, and, atthe same time, the transmission power is controlled by changing thetarget SIR through the outer loop.

Here, a total-transmission-power-value which is a transmission power forcommunication of the base station apparatus with a plurality ofcommunication terminals is required to be made equal to or smaller thana maximum transmission-power, as the maximum transmission-power of thebase station apparatus may not be made equal to or larger than apredetermined value by restrictions in amplification circuits such asamplifiers.

However, in a conventional base station apparatus, there has been a casein which the transmission power of the base station apparatus is nearthe maximum total-transmission-power value, as the transmission power isincreased in a simple manner in order to secure the communicationquality when there is an instruction from a communication terminal toincrease the transmission power, for example, due to deterioratedcommunication environments.

When the shortage of the transmission power is occurred, thecommunication quality is deteriorated by transmission at reducedtransmission power. Moreover, amplifiers and so on of the base stationapparatus are made in an unstable state as a system, when transmissionis continued almost in a limited condition, as the requirements toincrease the transmission power may not be met. Furthermore, there is aproblem that a new call may not be accepted due to shortage in thetransmission power.

DISCLOSURE OF INVENTION

The object of the present invention is to provide a base stationapparatus, a control station apparatus, and a method for controllingtransmission power, according to which a total-transmission-power-valueof the base station may be appropriately controlled, not depending onthe communication environments, and in a state securing thecommunication quality.

This object is realized by comparing a total-transmission-power-value,which is a sum of the power of signals transmitted to a plurality ofcommunication terminals at the same time, and areference-transmission-power-value, which is decided based on a maximumtransmission-power-value at which transmission is possible with acommunication apparatus such as an amplifier; by deciding allowabletransmission-power-values at which the signals transmitted to eachcommunication terminal are allowed to be transmitted; and bytransmitting the signals at transmission rates which are controlled foreach communication terminal, based on the allowabletransmission-power-values.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing a configuration of a base stationapparatus and a control station apparatus according to an embodiment 1of the present invention;

FIG. 2 is a flow chart showing a method for controlling thetotal-transmission-power in the base station apparatus and the controlstation apparatus according to the above embodiment;

FIG. 3 is a view showing one example of signals which are notified ateach layer by a method for controlling transmission rates in the basestation apparatus and the control station apparatus according to theabove embodiment;

FIG. 4 is a flow chart showing the method for controlling thetransmission rates in the base station apparatus and the control stationapparatus according to the above embodiment;

FIG. 5 is a view showing one example of signals which are notified ateach layer by a method for controlling total-transmission-power in thebase station apparatus and the control station apparatus according tothe above embodiment;

FIG. 6 is a flow chart showing a method for controlling thetotal-transmission-power in the base station apparatus and the controlstation apparatus according to the above embodiment;

FIG. 7 is a block diagram showing a configuration of a base stationapparatus and a control station apparatus according to an embodiment 2of the present invention;

FIG. 8 is a view showing one example of signals which are notified ateach layer by the method for controlling the total-transmission-power inthe base station apparatus and the control station apparatus accordingto the above embodiment;

FIG. 9 is a flow chart showing the method for controlling thetotal-transmission-power in the base station apparatus and the controlstation apparatus according to the above embodiment;

FIG. 10 is a block diagram showing a configuration of a base stationapparatus and a control station apparatus according to an embodiment 3of the present invention;

FIG. 11 is a flow chart showing a method for controlling thetotal-transmission-power in the base station apparatus and the controlstation apparatus according to the above embodiment;

FIG. 12 is a block diagram showing a configuration of a base stationapparatus and a control station apparatus according to an embodiment 4of the present invention;

FIG. 13 is a flow chart showing a method for controlling thetotal-transmission-power in the base station apparatus and the controlstation apparatus according to the above embodiment;

FIG. 14 is a block diagram showing a configuration of a base stationapparatus and a control station apparatus according to an embodiment 5of the present invention; and

FIG. 15 is a flow chart showing a method for controlling acceptance ofcall-processing in the base station apparatus and the control stationapparatus according to the above embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described,using drawings.

EMBODIMENT 1

In the present embodiment, a base station apparatus notifies a measuredtotal-transmission-power-value to a control station apparatus, and thecontrol station apparatus judges whether allowabletransmission-power-values to be set for each communication terminal arerequired to be changed or not according to the notifiedtotal-transmission-power-value. The control station apparatus changesthe allowable transmission-power-values if required based on the judgedresult. The base station apparatus controls thetransmission-power-values of each communication terminal, and thetotal-transmission-power-value of the whole base station apparatus byswitching of transmission rates based on the changed allowabletransmission-power-values.

FIG. 1 is a block diagram showing a configuration of the base stationapparatus and the control station apparatus according to the embodiment1 of the present invention.

In FIG. 1, a base station apparatus 100 mainly comprises: an antenna101; a duplexer 102; a receiving RF circuit 103; demodulation sections104; demultiplexing sections 105; individual-transmission-powercomparison sections 106; rate decision sections 107; transmissioncontrol sections 108; modulation sections 109;average-transmission-power measurement sections 110; code multiplexingsections 111; a transmitting RF circuit 112; and atotal-transmission-power measurement section 113.

And, a control station apparatus 150 comprises: areference-total-transmission-power setting section 151; atotal-transmission-power comparison section 152;allowable-transmission-power setting sections 153; and rate settingsections 154.

With regard to the demodulation sections 104, the demultiplexingsections 105, the individual-transmission-power comparison sections 106,the rate decision sections 107, the transmission control sections 108,the modulation sections 109, the average-transmission-power measurementsections 110, the allowable-transmission-power setting sections 153, andthe rate setting sections 154, the number of each section which isprovided is equal to the number of users, and similar operations areperformed at each section for users 1 through n.

The antenna 101 outputs a received radio signal as a received signal tothe duplexer 102, and transmits a transmission signal output from theduplexer 102 as a radio signal. The duplexer 102 outputs the receivedsignal input from the antenna 101 to the receiving RF circuit 103, and atransmission signal input from the transmission RF circuit 112 to theantenna 101.

The receiving RF circuit 103 amplifies the received signal input fromthe duplexer 102, and outputs the amplified signal to the demodulationsection 104 after frequency conversion into a baseband frequency. Thedemodulation sections 104 fetch user signals by despreading of thereceived signal input from the receiving RF circuit 103, and output theuser signals to the demultiplexing sections 105 after demodulation.

The demultiplexing sections 105 demultiplex the user signals input fromthe demodulation sections 104 into received data and transmission-ratecontrol signals (information on received quality) including controlinformation for switching of transmission rates, and output thetransmission-rate control signals to the individual-transmission-powercomparison sections 106, and the received data to the outside.

The individual-transmission-power comparison sections 106 compareaverage transmission-power-values input from theaverage-transmission-power measurement sections 110 which will bedescribed later, and allowable transmission-power-values input from theallowable-transmission-power setting sections 153 which will bedescribed later, and output to the rate decision sections 107instructions to change the transmission rates.

The rate decision sections 107 output appropriate transmission rates tothe transmission control sections 108 after selecting the appropriatetransmission rates in a rate set of a plurality of transmission rates,which is given from the rate setting sections 154, based on theinstructions, which are input from the individual-transmission-powercomparison sections 106. Specifically, when the transmission rates arereduced as the average transmission-power-values become equal to orlarger than the allowable transmission-power-values which have been set,the rate decision sections 107 select transmission rates which aresmaller by one rank or a plurality of ranks.

And, when the transmission rates are raised as the averagetransmission-power-values become smaller than the set allowabletransmission-power-values by X dB, the rate decision sections 107 selecthigher transmission rates which are corresponding to the differencesbetween the average transmission-power-values and the set allowabletransmission-power-values.

The transmission control sections 108 incorporate transmission data intoframes, and output the transmission frames to the modulation sections109 at transmission rates which are instructed from the rate decisionsections 107. The modulation sections 109 output obtained transmissionsignals to the code multiplexing section 111 after modulation andspreading of the transmission frames input from the transmission controlsections 108.

The code multiplexing section 111 multiplexes signals of a plurality ofusers input from the modulation sections 109, and outputs themultiplexed signal to the transmitting RF circuit 112. The transmissionRF circuit 112 amplifies the transmission signal input from the codemultiplexing section 11 after frequency conversion, and outputs theamplified signal to the duplexer 102.

The average-transmission-power measurement sections 110 measure theaverage power of the transmission signals input from the modulationsections 109, and output obtained average transmission-power-values tothe individual-transmission-power comparison sections 106.

The total-transmission-power measurement section 113 measures thetransmission power output from the transmitting RF circuit 112; obtainsa total-transmission-power-value which is a sum of the power of signalstransmitted by the base station apparatus at the same time; and outputsthe obtained total-transmission-power-value to thetotal-transmission-power comparison section 152. Thereference-total-transmission-power setting section 151 outputs areference total-transmission-power-value, which is a target of thetotal-transmission-power of the base station apparatus, and has beenpreviously set, to the total-transmission-power comparison section 152.

The total-transmission-power comparison section 152 obtains thedifference in the total-transmission-power by subtraction of thereference total-transmission-power-value, which has been output from thereference-total-transmission-power setting section 151, from thetotal-transmission-power-value input from the total-transmission-powermeasurement section 113, and outputs instructions to reduce theallowable transmission-power-values to allowable-transmission-powersetting sections 153 of the users 1–n, when the difference in thetotal-transmission-power exceeds a predetermined value.

The allowable-transmission-power setting sections 153 decide appropriateallowable transmission-power-values, based on the instructions from thetotal-transmission-power comparison section 152, and output the decidedallowable transmission-power-values to the individual-transmission-powercomparison sections 106.

The rate setting sections 154 set a rate set of a plurality oftransmission rates, and output the rate set to the rate decisionsections 107.

Then, operations of the base station apparatus 100 and the controlstation apparatus 150 according to the present embodiment will bedescribed.

The total-transmission-power-value is obtained in thetotal-transmission-power measurement section 113 as a sum of thetransmission power, and is output to the total-transmission-powercomparison section 152. The reference total-transmission-power-value isoutput from the reference-total-transmission-power setting section 151to the total-transmission-power comparison section 152.

The difference in the total-transmission-power is obtained in thetotal-transmission-power comparison section 152 by subtraction of thereference total-transmission-power-value from thetotal-transmission-power-value, and instructions to reduce the allowabletransmission-power-values are output to the allowable-transmission-powersetting sections 153 when the difference in the total-transmission-powerexceeds a predetermined value.

The allowable transmission-power-values are set in theallowable-transmission-power setting sections 153, and are output to theindividual-transmission-power comparison sections 106. When theinstructions to reduce the allowable transmission-power-values areoutput from the total-transmission-power comparison section 152 to theallowable-transmission-power setting sections 153, allowabletransmission-power-values which have been newly decided according to theinstructions to reduce the previous allowable transmission-power-valuesare output from the allowable-transmission-power setting sections 153 tothe individual-transmission-power comparison sections 106.

On the other hand, the radio signals transmitted from communicationterminals are received through the antenna 101 and the duplexer 102; areconverted into the baseband frequency in the receiving RF circuit 103;and are demultiplexed into the received data and pieces of informationon the received quality in the demultiplexing sections 105 afterdespreading and demodulation in the demodulation sections 104; and thepieces of information on the received quality are output to theindividual-transmission-power comparison sections 106.

And, the average transmission-power-values of signals transmitted fromeach user are obtained in the average-transmission-power measurementsections 110, and output to the individual-transmission-power comparisonsections 106.

When the average transmission-power-values input from theaverage-transmission-power measurement sections 110 are larger than theallowable transmission-power-values input from theallowable-transmission-power setting sections 153, instructions toreduce the transmission rates are output from theindividual-transmission-power comparison sections 106 to the ratedecision sections 107.

By the instructions to reduce the transmission rates, the base stationapparatus 100 transmits, for example, only the first half of one framewithout changing the transmission power itself. Or, transmission isperformed by the base station apparatus 100 without making the framediscontinuous by rate matching under the reduced transmission-powervalue. For example, burst transmission has been used for down links, andcontinuous transmission has been applied for up links in an existingmethod for changing transmission rates.

Therefore, the transmission rates are changed corresponding to theabove. That is, for example, only the first halt of one frame istransmitted as a transmission signal without changing thetransmission-power-value itself on the down links, and transmission isperformed on up links without making the frame discontinuous by ratematching under the reduced transmission-power value.

And, when the average transmission-power-values input from theaverage-transmission-power measurement sections 110 are equal to orsmaller than the allowable transmission-power-values output from theallowable-transmission-power setting sections 153 by predeterminedvalues, instructions to raise the transmission rates are output from theindividual-transmission-power comparison sections 106 to the ratedecision sections 107.

By the instructions to raise the transmission rates, the base stationapparatus 100 raises the transmission rates according to pieces ofinformation on the differences in the individual-transmission-powerrepresenting the differences between the allowable transmission-powerand the average transmission-power, and increases the transmission powerwithin a range of the differences in the individual-transmission-power.And, transmission signals which have been accumulated may be quicklytransmitted by raising the transmission rate.

Then, a method for controlling the total-transmission-power in the abovebase station apparatus 100 and the control station apparatus 150 withthe above configuration will be described, using a flow chart in FIG. 2.

At STEP (hereinafter, called as “ST”) 201, the total-transmission-powercomparison section 152 obtains the difference (D1) in thetotal-transmission-power, which is acquired by subtraction of thereference total-transmission-power-value (Ptarget), which has been inputfrom the reference-total-transmission-power setting section 151, fromthe total-transmission-power-value (Ptotal) input from thetotal-transmission-power measurement section 113. At ST202, thetotal-transmission-power comparison section 152 judges whether D1 islarger than 0 or not, and the operation is terminated when D1 is equalto, or smaller than 0.

At ST203, the total-transmission-power comparison section 152 outputs amessage saying “Having exceeded the referencetotal-transmission-power-value by D1 dB” to theallowable-transmission-power setting sections 153, when D1 is largerthan 0 at ST202. At ST204, the allowable-transmission-power settingsections 153 decide appropriate allowable transmission-power-values,based on the instructions output from the total-transmission-powercomparison section 152.

Then, a method for controlling the transmission rates in the basestation apparatus and the control station apparatus according to thepresent embodiment will be described. FIG. 3 is a view showing oneexample of signals which are notified at each layer by the method forcontrolling the transmission rates in the base station apparatus 100 andthe control station apparatus 150 according to the embodiment 1 of thepresent invention.

In FIG. 3, L1 (layer 1) represents a physical layer; L2 (layer 2) showsa media access control layer; and L3 (layer 3) means a radio resourcecontrol layer.

The control station apparatus 150 sets at the layer 3 rate sets ofselectable rates, and the allowable transmission-power-values, andnotifies them to the layer 3 of the base station apparatus.

The base station apparatus 100 notifies the rate sets, and the allowabletransmission-power-values, which have been notified to the layer 3, tothe layer 2. And, the average transmission-power-values measured at thelayer 1 of the base station apparatus are notified to the layer 2, atwhich the average transmission-power-values are compared with theallowable transmission-power-values, and the appropriate transmissionrates are decided in a given rate set.

Then, the method for controlling the transmission rates in the basestation apparatus 100 and the control station apparatus 150 with theabove configuration will be described, using a flow chart in FIG. 4.

At ST401, the rate setting sections 154 set the rate sets of selectablerates. At ST402, the allowable-transmission-power setting sections 153set the allowable transmission-power-values. At ST403, theaverage-transmission-power measurement sections 110 measures the averagetransmission-power-values. At ST404, the rate sets set by the ratesetting sections 154 are notified to the rate decision sections 107 atthe layer 2 of the base station apparatus through the layer 3 of thebase station apparatus.

At ST405, the allowable transmission-power-values set by theallowable-transmission-power setting sections 153 are notified to theindividual-transmission-power comparison sections 106 at the layer 2 ofthe base station apparatus through the layer 3 of the base stationapparatus. At ST406, the average transmission-power-values measured bythe average-transmission-power measurement sections 110 are notified tothe individual-transmission-power comparison sections 106. At ST407, theindividual-transmission-power comparison sections 106 compare theallowable transmission-power-values and the averagetransmission-power-values, and notify to the rate decision sections 107requests to change the transmission rates based on the compared results.

At ST408, the rate decision sections 107 decide the best transmissionrates in a given rate set, based on the requests to change thetransmission rates. At ST409, the transmission control sections 108transmit signals to each communication terminal, based on thetransmission rates decided in the rate decision sections 107.

Here, in this transmission control, for example, only the first half ofone frame is transmitted without changing the transmission power itself,as described above. Or, transmission is performed without making theframe discontinuous by rate matching under the reducedtransmission-power value.

Then, a method for controlling the total-transmission-power in the basestation apparatus 100 and the control station apparatus 150 of thepresent embodiment will be described. FIG. 5 is a view showing oneexample of signals which are notified at each layer by the method forcontrolling the total-transmission-power in the base station apparatus100 and the control station apparatus 150 according to the embodiment 1of the present invention.

In FIG. 5, L1 (layer 1) represents the physical layer; L2 (layer 2)shows the media access control layer; and L3 (layer 3) means the radioresource control layer.

The base station apparatus 100 measures thetotal-transmission-power-value in the total-transmission-powermeasurement section 113 at the layer 1, and notifies the measured valuesto the total-transmission-power comparison section 152 in the layer 3 ofthe control station apparatus 150 through the layer 3. The controlstation apparatus 150 compares the referencetotal-transmission-power-value notified from thereference-total-transmission-power setting section 151, and thetotal-transmission-power-value notified from the layer 3 of the basestation apparatus in the total-transmission-power comparison section152. The allowable transmission-power-values are changed based on thecompared results.

Then, a method for controlling the total-transmission-power in the basestation apparatus 100 and the control station apparatus 150 with theabove configuration will be described, using a flow chart in FIG. 6.

At ST601, the reference-total-transmission-power setting section 151sets the reference total-transmission-power-value, and notifies the setreference total-transmission-power-value to the total-transmission-powercomparison section 152. At ST602, the total-transmission-powermeasurement section 113 measures the total-transmission-power-value. AtST603, the total-transmission-power-value measured in thetotal-transmission-power measurement section 113 is notified to thetotal-transmission-power comparison section 152 at the layer 3 of thecontrol station apparatus through the layer 3.

At ST604, the total-transmission-power comparison section 152 comparesthe reference total-transmission-power-value and thetotal-transmission-power-value, and notifies requests to change theallowable transmission-power values based on the compared results to theallowable-transmission-power setting sections 153. At ST605, theallowable-transmission-power setting sections 153 change the allowabletransmission-power-values into appropriate allowabletransmission-power-values based on the requests to change the allowabletransmission-power-values.

At ST606, the allowable-transmission-power setting sections 153 notifythe allowable transmission-power-values changed through the layer 3 ofthe base station apparatus to the individual-transmission-powercomparison sections 106 at the layer 2 of the base station apparatus.

Here, the allowable transmission-power-values are changed for each useraccording to the flow chart shown in FIG. 2.

Thus, using the base station apparatus and the control station apparatusaccording to the present embodiment, the allowabletransmission-power-values to be set are changed for each communicationterminal according to changes in the total-transmission-power-valuewhich has been measured in the base station apparatus. As thetransmission rates are changed, based on the changed allowabletransmission-power-values, the total-transmission-power-value of thebase station apparatus may be kept at a predetermined value in a statesecuring the communication quality of each communication terminal.

Here, though the individual-transmission-power comparison sections 106and the rate decision sections 107 are arranged in the base stationapparatus 100, and the allowable-transmission-power setting sections 153and the rate setting sections 154 are arranged in the control stationapparatus 150 in FIG. 1, the arrangements of these components are notlimited to the above arrangements, and each group of the components maybe interchangeably arranged in the control station apparatus 150 or thebase station apparatus 100.

Moreover, the average transmission-power and thetotal-transmission-power may be measured not only in synchronousprocessing, but also in asynchronous processing. In this case, thechanges in the transmission rates according to the allowabletransmission-power-values, and the changes in the allowabletransmission-power-values by the total-transmission-power-values areasynchronously performed.

And, only the judgment whether “not change” or “reduction in the valuesbefore the changes” may be acceptable for setting the allowabletransmission-power-values. Moreover, instructions to reduce theallowable transmission-power-values, for example, by X dB may beincluded at setting of the allowable transmission-power-values. And, theallowable transmission-power-values may be changed by an amount inproportion to the difference between the total-transmission-power-valueand the reference total-transmission-power-value. In addition, a methodof reduction by a predetermined value may be used.

EMBODIMENT 2

In the present embodiment, a base station apparatus judges whetherallowable transmission-power-values to be set for each communicationterminal are required to be changed or not according to a measuredtotal-transmission-power-value. Only when the judged result requires thechanges, the base station apparatus notifies the request to change theallowable transmission-power-values to the control station apparatus,and the allowable transmission-power-values are changed by the controlstation apparatus. The base station apparatus controls thetransmission-power-values of each communication terminal, and thetotal-transmission-power-value of the whole base station apparatus byswitching of transmission rates based on the changed allowabletransmission-power-values.

FIG. 7 is a block diagram showing a configuration of the base stationapparatus and the control station apparatus according to the embodiment2 of the present invention. However, common components to those in FIG.1 are denoted by the same reference numbers as those in FIG. 1, anddetailed description will be eliminated. There is a difference betweenFIG. 7 and FIG. 1 in a point that a base station apparatus 700 in FIG. 7comprises a total-transmission-power comparison section 701 in which itis judged whether the allowable transmission-power-values are requiredto be changed or not.

In FIG. 7, a total-transmission-power measurement section 113 measurestransmission power input from a transmitting RF circuit 112; obtains atotal-transmission-power-value which is a sum of the power of signalstransmitted by the base station apparatus at the same time; and outputsthe obtained total-transmission-power-value to thetotal-transmission-power comparison section 701. Areference-total-transmission-power setting section 151 sets a referencetotal-transmission-power-value, which is a target of thetotal-transmission-power-value which is output by the base stationapparatus, and outputs the reference total-transmission-power-value tothe total-transmission-power comparison section 701.

The total-transmission-power comparison section 701 obtains, thedifference in the total-transmission-power by subtraction of thereference total-transmission-power-value, which has been input from thereference-total-transmission-power setting section 151, from thetotal-transmission-power-value input from the total-transmission-powermeasurement section 113, and outputs instructions to reduce theallowable transmission-power-values to allowable-transmission-powersetting sections 153 of users 1–n, when the difference in thetotal-transmission-power exceeds a predetermined value.

Then, a method for controlling the total-transmission-power in the basestation apparatus and the control station apparatus according to thepresent embodiment will be described. FIG. 8 is a view showing oneexample of signals which are notified at each layer by the method forcontrolling the total-transmission-power in the base station apparatus100 and the control station apparatus 150 according to the embodiment 2of the present invention.

In FIG. 8, L1 (layer 1) represents a physical layer; L2 (layer 2) showsa media access control layer; and L3 (layer 3) means a radio resourcecontrol layer.

The control station apparatus 750 sets the referencetotal-transmission-power-value in the reference-total-transmission-powersetting section 151 at the layer 3, and notifies the set referencetotal-transmission-power-value to the total-transmission-powercomparison section 701 at the layer 1 through the layer 3 of the basestation apparatus.

The base station apparatus 700 measures thetotal-transmission-power-value in the total-transmission-powermeasurement section 113 at the layer 1, and compares, in thetotal-transmission-power comparison section 701, the referencetotal-transmission-power-value notified from the control stationapparatus and the total-transmission-power-value measured in thetotal-transmission-power measurement section 113. When it is requiredafter the comparison to change the allowable transmission-power-values,the comparison result is notified to the allowable-transmission-powersetting sections 153 at the layer 3 of the control station apparatusthrough the layer 3. The allowable transmission-power-values which havebeen changed in the allowable-transmission-power setting sections 153when required are notified to individual-transmission-power comparisonsections 106 at the layer 2 through the layer 3 of the base stationapparatus

Then, the method for controlling the total-transmission-power in thebase station apparatus 700 and the control station apparatus 750 withthe above configuration will be described, using a flow chart in FIG. 9.

At ST901, the reference-total-transmission-power setting section 151sets the reference total-transmission-power-value. At ST902, thereference-total-transmission-power setting section 151 notifies the setreference total-transmission-power-value to the total-transmission-powercomparison section 701 at the layer 1 through the layer 3 of the basestation apparatus.

At ST903, the total-transmission-power measurement section 113 measuresthe total-transmission-power-value, and notifies the measured value tothe total-transmission-power comparison section 701. At ST904, thetotal-transmission-power comparison section 701 compares the referencetotal-transmission-power-value and the total-transmission-power-value.At ST905, the total-transmission-power comparison section 701 notifiesthe comparison result to the allowable-transmission-power settingsections 153 through the layer 3 of the base station apparatus.

At ST906, the allowable-transmission-power setting sections 153 changethe allowable transmission-power-values based on the requests to changethe total-transmission-power-value. At ST907, theallowable-transmission-power setting sections 153 notify the changedallowable transmission-power-values to the individual-transmission-powercomparison sections 106 at the layer 1 through the layer 3 of the basestation apparatus.

Here, the allowable transmission-power-values are changed for each useraccording to the flow chart shown in FIG. 2.

Thus, in the base station apparatus and the control station apparatusaccording to the present embodiment, requests to change the allowabletransmission-power-values are notified to the control station apparatus,in which the allowable transmission-power-values are changed, only whenit is required to change the allowable transmission-power-values to beset for each communication terminal according to changes in thetotal-transmission-power-value which has been measured in the basestation apparatus. As the transmission rates are changed, based on thechanged allowable transmission-power-values, thetotal-transmission-power-value of the base station apparatus may be keptat a predetermined value in a state securing the communication qualityof each communication terminal through exchange of smaller number ofcontrol signals between the control apparatus and the base stationapparatus.

Here, though the individual-transmission-power comparison sections 106and the rate decision sections 107 are arranged in the base stationapparatus 100, and the allowable-transmission-power setting sections 153and the rate setting sections 154 are arranged in the control stationapparatus 150 in FIG. 7, the arrangement of these components is notlimited to the above arrangements, and each group of the components maybe interchangeably arranged in the control station apparatus 150 or thebase station apparatus 100.

Moreover, the average transmission-power and thetotal-transmission-power may be measured not only in synchronousprocessing, but also in asynchronous processing.

In this case, the changes in the transmission rates according to theallowable transmission-power-values, and the changes in the allowabletransmission-power-values by the total-transmission-power-values areasynchronously performed.

EMBODIMENT 3

In the present embodiment, a control station apparatus decidestransmission-power-values of signals transmitted to each communicationterminal, using an instruction to change atotal-transmission-power-value, and priority information from a basestation apparatus.

FIG. 10 is a block diagram showing a configuration of the base stationapparatus and the control station apparatus according to the embodiment3 of the present invention. However, common components to those in FIG.1 are denoted by the same reference numbers as those in FIG. 1, anddetailed description will be eliminated. There is a difference betweenallowable-transmission-power setting sections 1051 in a control stationapparatus 1050 in FIG. 10, and allowable-transmission-power settingsections 153 in the control station apparatus 150 in FIG. 1 in a pointthat the allowable-transmission-power setting sections 1051 decideappropriate allowable transmission-power-values, based on priorityinformation which will be described later.

In FIG. 10, individual-transmission-power comparison sections 106compare average transmission-power-values input fromaverage-transmission-power measurement sections 110, and allowabletransmission-power-values input from the allowable-transmission-powersetting sections 1051 which will be described later, and output to ratedecision sections 107 instructions to change the transmission power.

A total-transmission-power comparison section 152 obtains the differencein the total-transmission-power by subtraction of a referencetotal-transmission-power-value, which has been input from areference-total-transmission-power setting section 151, from thetotal-transmission-power-value input from a total-transmission-powermeasurement section 113, and outputs instructions to reduce theallowable transmission-power-values to the allowable-transmission-powersetting sections 1051 of users 1–n, when the difference in thetotal-transmission-power is larger than 0.

The allowable-transmission-power setting sections 1051 decideappropriate allowable transmission-power-values, based on theinstructions from the total-transmission-power comparison section 152,and pieces of priority information which are information on priority bywhich power values of signals transmitted to each user, and output thedecided allowable transmission-power-values to theindividual-transmission-power comparison sections 106.

For example, the priority information is set according to conditionssuch as QoS (Quality of Service) of users, the kind of service, and adata transfer method at the layers 2. As one example, when two levels ofHigh and Low are adopted as the priority information, the allowabletransmission-power-values are assumed to be variable only for users withthe High-level priority information, and there is no change in theallowable transmission-power-values for users with the Low-levelpriority information, even when requests to change the allowabletransmission-power-values are notified from the total-transmission-powercomparison section 152. Moreover, for example, the changes in theallowable transmission-power-values are set according to the priority,when there are a plurality of ranks in the priority.

Then, a method for controlling the total-transmission-power in the basestation apparatus 100 and the control station apparatus 1050 with theabove configuration will be described, using a flow chart in FIG. 11.

At ST1101, the reference-total-transmission-power setting section 151sets the reference total-transmission-power-value, and the set referencetotal-transmission-power-value is notified to thetotal-transmission-power comparison section 152. At ST1102, thetotal-transmission-power measurement section 113 measures thetotal-transmission-power-value. At ST1103, thetotal-transmission-power-value which the total-transmission-powermeasurement section 113 has measured is notified to thetotal-transmission-power comparison section 152 at the layer 3 of thecontrol station apparatus through the layer 3. At ST1104, thetotal-transmission-power comparison section 152 compares thetotal-transmission-power-value and the referencetotal-transmission-power-value, and requests to change the allowabletransmission-power-values, based on the compared result, are notified tothe allowable-transmission-power setting sections 1051.

At ST1105, the allowable-transmission-power setting sections 1051 judgewhether the allowable transmission-power-values are required to bechanged based on the priority information for each user. When theallowable transmission-power-values are not required to be changed onthe judged results, the processing is terminated. When the allowabletransmission-power-values are required to be changed, the allowabletransmission-power-values are changed at ST1106, based on the priorityinformation, and the comparison results from thetotal-transmission-power comparison section 152.

At ST1107, the allowable transmission-power-values which theallowable-transmission-power setting sections 1051 have changed throughthe layer 3 of the base station apparatus are notified to theindividual-transmission-power comparison sections 106 at the layer 2 ofthe base station apparatus.

Here, the allowable transmission-power-values are changed for each useraccording to the flow chart shown in FIG. 2.

Thus, in the base station apparatus and the control station apparatusaccording to the present embodiment, changes in the allowabletransmission-power-values are decided for each terminal, based oninstructions requesting to change the allowabletransmission-power-values and the priority information which has beenpreviously set for each user, when the fluctuatingtotal-transmission-power-value of the base station apparatus exceeds thereference total-transmission-power-value, and thetotal-transmission-power-value of the base station apparatus may be moreprecisely controlled corresponding to communication conditions of eachuser in a state securing the communication quality of each communicationterminal through switching of the transmission rates according to thechanged allowable transmission-power-values.

EMBODIMENT 4

In a base station apparatus and a control station apparatus according tothe present embodiment, requests to change allowabletransmission-power-values are notified to the control station apparatus,only when the set allowable transmission-power-values to be set for eachcommunication terminal are required to be changed according to changesin a total-transmission-power-value measured in the base stationapparatus, and the control station apparatus changes for eachcommunication terminal the allowable transmission-power-values, based onrequests from the base station apparatus to change the allowabletransmission-power, and on priority information for each user.Transmission-power values of each communication terminal are controlledby switching transmission rates based on the changed allowabletransmission-power-values, and the total-transmission-power-value of thewhole base station is controlled.

FIG. 12 is a block diagram showing a configuration of the base stationapparatus and the control station apparatus according to the embodiment4 of the present invention. However, common components to those in FIG.1 are denoted by the same reference numbers as those in FIG. 1, anddetailed description will be eliminated. There is a difference betweenFIG. 12 and FIG. 1 in a point that a base station apparatus 1200 in FIG.12 comprises a total-transmission-power comparison section 1201 in whichit is judged whether the allowable transmission-power-values arerequired to be changed or not. And, there is another difference betweenFIG. 12 and FIG. 1 in a point that allowable-transmission-power settingsections 1251 in FIG. 12 decide appropriate allowable transmission-powervalues based on priority information which will be described later.

In FIG. 12, individual-transmission-power comparison sections 106compare average transmission-power-values input fromaverage-transmission-power measurement sections 110, and the allowabletransmission-power-values input from the allowable-transmission-powersetting section 1251, and output instructions to change the transmissionpower to a rate decision sections 107.

A total-transmission-power measurement section 113 measures transmissionpower input from a transmitting RF circuit 112; obtains thetotal-transmission-power-value which is a sum of the power of signalstransmitted by the base station apparatus at the same time; and outputsthe obtained total-transmission-power-value to thetotal-transmission-power comparison section 1201.

A reference-total-transmission-power setting section 151 sets areference total-transmission-power-value, which is a target of thetotal-transmission-power-value which is output by the base stationapparatus, and outputs the reference total-transmission-power-value tothe total-transmission-power comparison section 1201.

The total-transmission-power comparison section 1201 obtains thetotal-transmission-power-value by subtraction of the referencetotal-transmission-power-value input from thereference-total-transmission-power setting section 151, from thetotal-transmission-power-value input from the total-transmission-powermeasurement section 113, and outputs instructions to reduce theallowable transmission-power-values to the allowable-transmission-powersetting sections 1251 of users 1–n, when the difference in thetotal-transmission-power is larger than 0.

The allowable-transmission-power setting sections 1251 decideappropriate allowable transmission-power-values, based on theinstructions output from the total-transmission-power comparison section1201, and pieces of priority information which are information onpriority orders by which the allowable transmission-power-values arechanged, and output the decided allowable transmission-power-values tothe individual-transmission-power comparison sections 106.

Then, a method for controlling the total-transmission-power in thecontrol station apparatus 1250 with the above configuration will bedescribed, using a flow chart in FIG. 13.

At ST1301, the reference-total-transmission-power setting section 151sets the reference total-transmission-power-value. At ST1302, thereference-total-transmission-power setting section 151 notifies the setreference total-transmission-power-value to the total-transmission-powercomparison section 1201 at the layer 1 of the base station apparatusthrough the layer 3 of the base station apparatus.

At ST1303, the total-transmission-power measurement section 113 measuresthe total-transmission-power-value, and notifies the measured value tothe total-transmission-power comparison section 1201. At ST1304, thetotal-transmission-power comparison section 1201 compares thetotal-transmission-power-value and the referencetotal-transmission-power-value. At ST1305, the total-transmission-powercomparison section 1201 notifies the compared result to theallowable-transmission-power setting sections 1251 through the layer 3of the base station apparatus.

At ST1306, the allowable-transmission-power setting sections 1251 judgewhether the allowable transmission-power-values are required to bechanged or not based on the priority information for each user. When theallowable transmission-power-values are not required to be changed onthe judged results, the processing is terminated. When the allowabletransmission-power-values are required to be changed, the allowabletransmission-power-values are changed at ST1307, based on the priorityinformation and the comparison result from the total-transmission-powercomparison section 1201.

At ST1308, the allowable-transmission-power setting sections 1251 notifythe allowable transmission-power-values, which have been changed throughthe layer 3 of the base station apparatus, to theindividual-transmission-power comparison section 106 at the layer 2 ofthe base station apparatus.

Thus, in the base station apparatus and the control station apparatusaccording to the present embodiment, requests to change the allowabletransmission-power-values are notified to the control station apparatus,only when it is required to change the allowabletransmission-power-values to be set for each communication terminalaccording to changes in the total-transmission-power-value measured inthe base station apparatus; and the control station apparatus changesthe allowable transmission-power-values to be set for each terminal,based on instructions requesting to change the allowabletransmission-power-values, and the priority information. Thetotal-transmission-power-value of the base station apparatus may be moreprecisely controlled corresponding to communication conditions in astate securing the communication quality through switching of thetransmission rates based on the changed allowabletransmission-power-values, and through exchange of smaller number ofcontrol signals between the control apparatus and the base stationapparatus.

EMBODIMENT 5

A base station apparatus and a control station apparatus of the presentembodiment predict increase in transmission power at accepting of a callfrom a new user, and judge whether the increase in the transmissionpower is within an allowable range or not. FIG. 14 is a block diagramshowing a configuration of the base station apparatus and the controlstation apparatus according to the embodiment 5 of the presentinvention. However, common components to those in FIG. 1 are denoted bythe same reference numbers as those in FIG. 1, and detailed descriptionwill be eliminated.

There is a difference between FIG. 14 and FIG. 1 in a point that acontrol station apparatus 1450 in FIG. 14 comprises a memory 1452 and acall-accepting control section 1453; predicts a transmission-power valuewhich will be increased by accepting a call from a new user; and judgeswhether the increase in the transmission-power value is within anallowable range for the base station apparatus to accept the call ornot.

Then, function blocks for controlling the total-transmission-power willbe described. A total-transmission-power measurement section 113measures a total-transmission-power-value, and outputs thetotal-transmission-power-value to a total-transmission-power comparisonsection 1451. A reference-total-transmission-power setting section 151sets a reference total-transmission-power-value, and outputs the setreference total-transmission-power value to the total-transmission-powercomparison section 1451.

The total-transmission-power comparison section 1451 compares thereference total-transmission-power-value input from thereference-total-transmission-power setting section 151, and thetotal-transmission-power-value input from he total-transmission-powermeasurement section 113; outputs instructions to change the transmissionpower to allowable-transmission-power setting sections 1454; and outputsa difference in the total-transmission-power which is a differencebetween the total-transmission-power-value and the referencetotal-transmission-power-value to the memory 1452.

The memory 1452 stores the difference in the total-transmission-powerwhich is the difference between the total-transmission-power-value andthe reference total-transmission-power-value.

When the call from the new user is accepted, the call-accepting controlsection 1453 requests the difference in the total-transmission-power atthis point to the memory 1452, and acquires the requested difference;adds a power value (Puser), which the new user desires, to thedifference in the total-transmission-power; and obtains the differencein the total-transmission-power after the addition of the power. Here,the difference in the total-transmission-power after the addition of thepower is almost equal to the difference between thetotal-transmission-power-value and the referencetotal-transmission-power-value after accepting the call from the newuser.

And, the call-accepting control section 1453 accepts the call when it isjudged, based on the difference in the total-transmission-power afterthe addition of the power, that there is a margin in thetransmission-power-value for accepting the new user, considering thereference total-transmission-power-value; and outputs the difference inthe total-transmission-power after the addition of the power to theallowable-transmission-power setting sections 1454.

The allowable-transmission-power setting sections 1454 set the allowabletransmission-power-values, based on the difference in thetotal-transmission-power after the increase in the power. For example,when it is judged that there is a small margin in the transmission-powervalue for accepting the new user, that is, when the difference in thetotal-transmission-power, which is input from the call-accepting controlsection 1453, after the addition of the power is very small, theallowable-transmission-power setting sections 1454 set rather smallallowable transmission-power-values for the user so that thetotal-transmission-power-value of the whole base station apparatus doesnot exceed the reference total-transmission-power-value.

Moreover, when it is judged that there is no margin in thetransmission-power for accepting the new user, based on the differencein the total-transmission-power at a point in which the request toaccept the call is received, and on power value (Puser) which the newuser desires, the call-accepting control section 1453 rejects the call.

The allowable-transmission-power setting sections 1454 set appropriateallowable transmission-power-values, based on the difference, which isreceived from the call-accepting control section 1453, in thetotal-transmission-power after the addition of the power. Once the callis accepted, the allowable-transmission-power setting sections 1454 set,in a similar manner to that of the embodiment 1, the allowabletransmission-power-values, based on the difference in thetotal-transmission-power at a point in which the difference is outputfrom the total-transmission-power comparison section 1451.

Then, a flow for processing in the call-processing control section 1453will be described, using FIG. 15.

At ST1501, the call-processing control section 1453 refers to thedifference D1 between the total-transmission-power-value and thereference total-transmission-power-value stored in the memory 1452 ataccepting the new call. At ST1502, the call-processing control section1453 adds a desired power value (Puser), which would be increased ataccepting the new user, to D1, and obtains the difference in thetotal-transmission-power (D2) after the addition of the power.

At ST1503, it is judged whether D2 is larger than 0 or not. When D2 islarger than 0, that is, when the total-transmission-power-value afterthe addition of the power is larger than the referencetotal-transmission-power-value, the call-accepting control section 1453rejects the call at ST1504. When D2 is equal to or less than 0 atST1503, a message saying “the total-transmission-power-value is lowerthan the reference total-transmission-power-value by lD2l dB” is shownat ST1505; the call-processing control section 1453 accepts the newuser; and D2 is output to the allowable-transmission-power settingsections 1454.

Thus, according to the base station apparatus and the control stationapparatus of the present embodiment, judgement for accepting a new callis performed by predicting increase in transmission power, and byjudging whether the total-transmission-power-value after addition of theincrease is within an allowable range or not. When thetotal-transmission-power-value exceeds the referencetotal-transmission-power-value, the system is in a limit state. In thiscase, it is possible, not by controlling thetotal-transmission-power-value through reducing the allowabletransmission-power-values of a lot of users after accepting the newcall, but by not-accepting the new call, to prevent reduction in theallowable transmission-power-values of users under currentcommunication, that is, the maximum transmission rates at whichtransmission is possible.

Here, there is a shortage of resources as a system, when the differencebetween the total-transmission-power-value and the referencetotal-transmission-power-value is small, though thetotal-transmission-power-value does not exceed the referencetotal-transmission-power-value. In this case, more users than those in ausual system can be accepted by setting an allowabletransmission-power-value, which is smaller than the difference betweenthe total-transmission-power-value and the referencetotal-transmission-power-value, as an initial value even in a state inwhich acceptance of a new call is usually rejected.

In addition, the inventors of the present invention have previously madean invention, in which the transmission-power-values of the base stationfor communication terminals are appropriately controlled, not dependingon the environments and the transmission rates of communicationterminals, as more data are transmitted at raised transmission rates ingood channel states, and amount of transmission data is suppressed byreducing the transmission rates in poor channel states by switching oftransmission rates of transmission signals based on information onreceived quality from communication terminals, that is, according to theenvironments of the communication terminals, and by transmission oftransmission signals at the switched transmission rates. The aboveinvention has been disclosed in the Japanese Patent Application2000-025602.

Then, the base station apparatus and the control station apparatusaccording to the present invention may be configured, in a similarmanner to that of the above invention, so that changes in allowabletransmission-power-values to be set for each communication terminal areinstructed based on comparison between a total-transmission-power-valueand a reference total-transmission-power-value; transmission rates oftransmission signals are switched based on information on receivedquality from the communication terminals, that is, corresponding to theenvironments of the communication terminals; and the transmissionsignals are transmitted at the switched transmission rates.

And, a method for changing power values of signals to be transmitted toeach communication terminal is not specially limited, and any methodsfor the above object may be applied to the present invention iftransmission rates or transmission power may be controlled according toinstructions to change transmission power values.

As it is clear from the above description, thetotal-transmission-power-value of the base station is appropriatelycontrolled, not depending on the environments and the transmission ratesof communication terminals in the base station apparatus, the controlstation apparatus, and the method for controlling transmission poweraccording to the present invention, as the allowabletransmission-power-values to be set for each communication terminal aredecided according to changes in the total-transmission-power-value ofthe base station, and the transmission rates are decided by the decidedallowable transmission-power-values.

The present description is based upon claims from the prior JapanesePatent Application 2000-259510, filed on Aug. 29, 2000. The entirecontents are incorporated herein by reference.

INDUSTRIAL APPLICABILITY

The present invention is preferably used for a base station apparatusand a control station apparatus used in a digital radio communicationsystem.

1. A base station apparatus comprising: total-transmission-powermeasurement means for measuring a total-transmission-power-value whichis a sum of transmission power of signals transmitted to a plurality ofcommunication terminals at the same time; comparison means foroutputting instructions to reduce allowable transmission-power to acontrol station apparatus when said total-transmission-power-value islarger than a reference total-transmission-power-value which has beenpreviously set; and transmission control means for deciding transmissionrates of the signals for each communication terminal apparatus, based onallowable transmission-power-values which have been output from saidcontrol station apparatus.
 2. A control station apparatus comprising:comparison means for judging whether allowable transmission power isrequired to be reduced or not when a total-transmission-power-valueoutput from a base station apparatus is larger than a referencetotal-transmission-power-value which has been previously set; andallowable-transmission-power setting means for setting, for eachcommunication terminal, allowable transmission-power-values, whichrepresent allowable power of signals based on said judgment, and foroutputting the set values to said base station apparatus, wherein saidbase station apparatus comprises: total-transmission-power measurementmeans for measuring the total-transmission-power-value which is a sum oftransmission power of said signals transmitted to a plurality ofcommunication terminals at the same time, and for outputting themeasured values to said control station apparatus; and transmissioncontrol means for deciding transmission rates of the signals for eachcommunication terminal, based on allowable transmission-power-values,which have been output from said control station apparatus, for eachcommunication terminal apparatus.
 3. A control station apparatusaccording to claim 2, wherein in said allowable-transmission-powersetting means, said allowable transmission-power-values are assumed tobe a value obtained by multiplication of said allowabletotal-transmission-power-values by a transmission-power ratio obtainedby division of said transmission power of each communication terminalapparatus by said total-transmission-power-value, when saidtotal-transmission-power-value exceeds said referencetotal-transmission-power-value.
 4. A control station apparatus accordingto claim 2, wherein in said allowable-transmission-power setting means,said allowable transmission-power-values are set to be a value obtainedby subtraction with a value, which has been previously set, to bechanged, when said total-transmission-power-value exceeds said referencetotal-transmission-power-value.
 5. A control station apparatus accordingto claim 2, wherein said allowable-transmission-power setting meansdecides said allowable total-transmission-power-values by weightingbased on priority information.
 6. A control station apparatus accordingto claim 2, comprising call-processing control means for estimatingincrease in said total-transmission-power-value by accepting a new call,and for accepting the new call when said increase in saidtotal-transmission-power-value is equal to or smaller than a differencebetween said reference total-transmission-power-value and saidtotal-transmission-power-value.
 7. A control station apparatus accordingto claim 6, wherein said call-processing control means estimatesincrease in said total-transmission-power-value by accepting a new call,and sets said allowable transmission-power which is smaller than saiddifference between said reference total-transmission-power-value andsaid total-transmission-power-value when said increase in saidtotal-transmission-power-value is equal to or larger than saiddifference between said reference total-transmission-power-value andsaid total-transmission-power-value.
 8. A control station apparatuscomprising allowable-transmission-power setting means for settingallowable transmission values for each communication terminal apparatusbased on instructions output from a base station apparatus to reduceallowable transmission-power, and for outputting the set values to saidbase station apparatus, wherein said base station apparatus comprises:total-transmission-power measurement means for measuring atotal-transmission-power-value which is a sum of transmission power ofsignals transmitted to a plurality of communication terminals at thesame time; comparison means for outputting an instruction to reduceallowable transmission power to said control station apparatus, whensaid total-transmission-power-value is larger than a referencetotal-transmission-power-value which has been previously set; andtransmission control means for deciding transmission rates of thesignals for each communication terminal, based on said allowabletransmission-power-values output from said control station apparatus. 9.A control station apparatus according to claim 8, wherein in saidallowable-transmission-power setting means, said allowabletransmission-power-values are assumed to be a value obtained bymultiplication of said allowable total-transmission-power-values bytransmission-power ratios obtained by division of said transmissionpower of each communication terminal apparatus by saidtotal-transmission-power-value, when said total-transmission-power-valueexceeds said reference total-transmission-power-value.
 10. A controlstation apparatus according to claim 8, wherein in saidallowable-transmission-power setting means, said allowabletransmission-power-values are set to be a value obtained by subtractionwith a value, which has been previously set, to be changed, when saidtotal-transmission-power-value exceeds said referencetotal-transmission-power-value.
 11. A control station apparatusaccording to claim 8, wherein said allowable-transmission-power settingmeans decides said allowable total-transmission-power-values byweighting based on priority information.
 12. A control station apparatusaccording to claim 8, comprising call-processing control means forestimating increase in said total-transmission-power-value by acceptinga new call, and for accepting the new call when said increase in saidtotal-transmission-power-value is equal to or smaller than a differencebetween said reference total-transmission-power-value and saidtotal-transmission-power-value.
 13. A control station apparatusaccording to claim 12, wherein said call-processing control means forestimating said increase in said total-transmission-power-value byaccepting said new call, and for setting said allowable transmissionpower which is smaller than said difference between said referencetotal-transmission-power-value and said total-transmission-power-valuewhen said increase in said total-transmission-power-value is equal to orlarger than said difference between said referencetotal-transmission-power-value and said total-transmission-power-value.